Sandy....many healing vines to Boris. His story sounds somewhat familiar as my darling GA Sitka passed away from CHF. She was the healthiest cat her entire life but shortly after she turned 21, she started having kidney issues. I had an echocardiogram of her heart done just to make sure that fluids would not be a problem and her echo was completely normal; we started a modest amount of fluids. However, she did develop CHF. They tapped her chest three times in a month but it kept filling even faster after each time even though we had stopped giving fluids. The IM specialist did not want to give much lasix because of her kidneys. Despite the chest taps, she was doing really well ....eating, responding to us...her QOL seemed great. One night I tucked her in her bed and kissed her goodnight and she seemed to be doing well...very responsive, no difficulty breathing. When I awoke at 5 am, I could tell something had happened....probably a heart attack but she was still alive like she was waiting for me. I held her in my arms and she breathed her last few breaths....it was so peaceful and quiet and the kind of passing I had always hoped for her....in her home, in my arms, no pain. I don't know if this always happens with CHF but it was a blessing for us and for her....she chose when to go. I tell you this not to upset you more but to let you know that it isn't always a horrible end....the vet did not think that she "drowned" in the fluid as they had just recently tapped her chest and even when I found her, she did not have labored breathing. She just slipped away. I will hope the best for your Boris.